<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
</head>
<body>

</body>
</html>

<script>
	var arr=[[1,2],["hello","yet"],[true,false],100];
	//alert(arr[2][0]);

	var arr1 = new Array(25);

	for(var i=0;i<25;i++){
		arr1[i]=i+1;
	}

	var newarr=[];
	for(var j=0;j<5;j++){
		newarr.push(arr1.splice(0,5));
	}
	alert(newarr)

	for(var i=0;i<5;i++){
		for(var j=0;j<=i;j++){
			document.write(newarr[i][j]+"&nbsp;")
		}
		document.write("<br/>");
	}

</script>